Refrigerated centrifuge



Dec. 15, 1959 c. Dx BENEDETTO ET AL 2,917,229

REFRIGERATED CENTRIFUGE Filed April 17, 195s Unite 2,917,229REFRIGERATED CENTRIFUGE Charles Di Benedetto and William J. Piemonte,Brooklyn, and Salvatore Di Benedetto, Franklin Square, N Y., assignorsto Lourdes Instrument, Company, Brooklyn, N.Y.

Application April 17, 1958, Serial No. 730,748 2 Claims. (Cl. 233-11)art; however, the prior attempts all provide cooling by means of acylindrical sleeve type evaporator. With this type cooling there isconsiderable air turbulence and poor circulation, which may result ininefficient refrigeration. Also, the prior art shows that the ksurfacecooling area is limited to the area of the cylindrical jacket.

It is an object of this invention to provide a centrifuge in which thehigh speed rotor is also the air impeller for the circulation of airthrough and around a plurality of refrigerated coils and back to therotor to provide the desired cooling of the rotor.

It is a further object of this invention to provide a centrifuge inwhich the high speed rotor is also the air impeller for the circulationof air through and around a plurality of refrigerated coils and back tothe rotor to provide the desired cooling of the rotor and in which thedegree of air flow is in direct proportion to the r.p.m. of the rotor.

y.It is a-further object of this invention to provide a centrifuge inwhich the high speed rotor is also the air impeller for the circulationof air through and around a plurality of refrigerated coils and back't'othe rotor to provide the desired cooling of the rotor and in which thedegree of air flow is in direct proportion to the r.p.m. of the rotorand is directed in two paths, vone stream of air passing through siderefrigerated coils and being redi- States Patent O rected back to thetop and side of the rotor while the A Vother stream of air is directedthrough bottom refrigerated coils and redirected to impinge on thebottom surface of the rotor to provide the desired cooling of the rotor.

It is a still further object of this invention to provide a centrifugethat is mounted within a refrigerated cabinet'and in which the highspeed rotor becomes the impeller for circulating air within the cabinetthrough a -plurality of refrigerated coils and in which the air streamshape of the rotor and the degree of air flow is controlled by ther.p.m. of the rotor and the air flow is divided into two air streams,one stream of air passing through the side refrigerated coils and beingdirected back to the top and side of the rotor while the other stream ofair is directed through bottom refrigerated coils and redi- ICC rectedback to mpinge on the bottom surface of the rotor to provide the desiredcooling of the rotor.

It is a still further object of this invention to provide a centrifugethat is mounted Within a refrigerated cabinet and in which the highspeed rotor becomes the impeller for circulating air within the cabinetthrough a plurality of refrigerated coils and in which the air stream isproperly deflected to provide laminar ow through a plurality ofrefrigerated coils.

It is a still further object of this invention to provide a centrifugethat ismounted within a refrigerated cabinet and in which the high speedrotor becomes the impeller forv circulating air within the cabinetthrough a plurality of refrigerated coils and in which the air stream isproperly dellected to provide laminar ow through a plurality of primaryand secondary refrigerated surfaces.

It is a still further object of this invention to provide a centrifugethat is mounted within a refrigerated cabinet and in which the highspeed rotor becomes the impeller for circulating air within the cabinetthrough a plurality of refrigerated coils and in which the air stream isproperly dellected to provide laminar llow through a plurality of largearea refrigerated coils with primary an secondary cooling surfaces.

It is a still further object of this invention to provide a centrifugethat is mounted within a refrigerated cabinet and in which the highspeed rotor becomes the impeller for circulating air within the cabinetthrough a plurality of refrigerated coils and in which the air stream isproperly deflected to provide laminar flow through a plurality of bottomas well as side refrigerated coils.

Further objects of this invention shall be apparent by reference to theaccompanying detailed description and the drawings in which:

Figure 1 is a cross sectional view of the centrifuge mounted in arefrigerated cabinet.

Figure 2 is a plan view taken on line 2 2 of Figure l.

Referring to the drawing, there is illustrated a stationary circularsupporting cabinet 10. The cabinet 10 has a circular wall 11 and abottom 12. The bottom or base of the cabinet 12 is provided With aconcentric aperture 14. The top of the cabinet is provided with a flange15 which is approximately 90 to the wall 11. A cylindrical liner 16,preferably of stainless steel, is provided to fit into the cabinet andabut with the edge of the circular flange 15. The liner 16 may be turnedover and bolted to flange 15. This joint also provides the means ofclamping a rubber gasket 17 as illustrated so that a cover 19 may bepositioned over the cabinet in use. The liner 16 does not extend to thebottom of the cabinet. It is approximately 2/3 of the depth of thecabinet and the liner 16 is provided with a plurality of slots orapertures 20 adjacent the upper edge of liner 16. Within the spaceformed by the circular wall 11 and the circular liner 16, there aremounted a plurality of tubes 21. Tubing 21 is preferably spiraled aboutthe cabinet in the position illustrated and it is in turn connected to arefrigeration system so that the refrigerated gas,tsuch as Freon 22,will be pumped through the tubing and the expansion of the Freon willtake place Within the tubing. The tubing 21 is also provided with aplurality of fins 22 in disk form or the ns may also be spiraled aboutthe tubing 21. In the base of cabinet 10, there is also mounted acircular'deflection plate 23. The upper edge of the dellection plate 23abuts with the wall 11 of the cabinet, while the lower edge of thedeliection plate 23 abuts with and rests upon the bottom wall 12. Thedeflection plate 23 is provided with a plurality of apertures 24. It isto be noted that the apertures 24 are formed by cutting the plate 23 andforming or bending the metal inward, to form a curved baffle 25. It iskalso to be notedl thata pluralityof apertures are punched in thedeection plate at a position in close proximity with the bottom edge ofthe plate as illustrated. Apertures may be circular in form as shown orthey ,may be enlarged in slot form to provide sutiicient opening for thepassageiof the refrigerated or cooled air. It is to be noted that withinthe area formedby the wall 11 of the cabinet, the base or bottom 12 ofthe cabinet and the deflection plate 23, there are a plurality ofrefrigerated coils mounted. These coils are similar to thosevmounted inthe upper portion of the cabinet. lt

. vis to be noted that the tubing 21 may be equally spaced along thewall 11 and the bottom 12.

With the cabinet as described, the centrifuge rotor and support assembly3G may be centrally mounted within the cabinet. In this particularinstance a base 31. is mounted in the cabinet to rest upon the bottomV12 and the Aiiange or deflection plates 23. Base 31 is provided with acentral aperture 32 to permit a drive shaft (not shown) to be passedtherethrough for driving the centrifuge. A supporting structure 33 ismounted on base .31, structure 33 supporting thrust bearings 34.Structure 33 is formed with a smaller concentric portion 35 that fitswithin the lower bore 36 of a rotor 37. The thrust bearngsS-t support adrive shaft 38, ,drive shaft 38 extending through the smaller bore 39 ofthe rotor 37. AThe rotor 37 is provided with angularly shaped walls tuand a flat cover 41. It is to `be noted that the rotor 37 in its mountedand supported position is retained with a spacing between the bottom ofthe rotor 37 and its supporting structure. This is to permit a freecirculation of air aroundthe bottom of the rotor.

With the device as described it is apparent that the rotor 37 isconcentrically balanced within the cabinet and driven by means of adrive shaft 38 that is supported in a thrust bearing 34 and with thecover 19 closed down upon the gasket 17, the cabinet will be sealed withthe refrigeration system (not shown) connectedto the tubing 2.1 andoperating to provide the required degree of refrigeration for thesystem. When the rotor 37 is driven at its minimum or maximum rpm. therotation of rotor 37 has the effect of impelling or moving the airsurrounding said rotor. The high r.p.m. produces a throwing off of theair at the greatest diameter of the rotor. As indicated by arrows, theair will be cast off by centrifugal force and will impinge against thedeflection plate 23. The air would normally be directed upward accordingto the arrows passing around the refrigerated coils 21 and upwardthrough the area bounded by wall ill of the cabinet and the liner 16. Asthe ow of air builds up within this area it will be redirected throughthe apertures Ztl at the top of liner 16 and since the high r.p.m. ofthe rotor induces considerable velocity to the air, the air will ow at arapid rate and will be thrown out of the apertures 2t) to impinge uponthe cover 41 and the angular walls 4t? of the rotor. The air will absorbthe heat from the rotor and will be circulated to be again coiled as itpasses around refrigerated coils.

Referring to the deection plate 23 and particularly the apertures 24 andthe deiiecting bafes 25, it is apparent that a certain portion of theair stream will be directed through these apertures to circulate withinthe area below the deliection plate passing around the refrigeratedcoils and being redirected through the apertures 26 and due to thevelocity iiow of the air will pass from apertures 26 upward and impingeupon the lower surface of rotor 37. The cabinet 10 at the area where thewall 11 and base 12 join, may be curved to assist the natural air oW andprevent turbulence. Likewise Where the air passes through apertures 24,a further curved deflection guard 45 may be added to also assist incontrolling the air ow and prevent turbulence. It is apparent that asthe rotor 37 is operated, the minimum r,p.m. operation is sufiicient toprovide the desired air circulating for cooling the rotor. However, asthe rotor 1-37 is increased in its r.p.m., it also tends to heat to agreater degree and the increased r.p.m. also creates a greater velocityow of air and thus produces a greater degree of cooling so that theincrease in degree of heat created is easily and properly taken care ofby the increased cooling elect produced by the increased air flow. Aslong as the refrigerated coils are adequately cooled, there will be avery effective cooling of the rotor 37, regardless of the r.p.m. atwhich it is driven (from minimum to maximum as designed).

Although the refrigerated cabinet described is provided withrefrigerated coils of tubing, the cabinet may be similarly provided withother types of radiating elements as long as the radiating elements arepositioned within the area of the air stream withoutdeparting from thespirit of this invention and although the rotor is designed primarilyfor centrifuge operation, the rotor may be utilized to provide the dualfunction of impelling a circulation of air and the shape of the rotormay be altered to a greater or lesser angular degree to assist or changethe degree of circulation without departing from the spirit of thisinvention, and although the cabinet has been designed to provide adivision of the air being circulated to provide two paths ofcirculation, the air may be divided into a plurality of other paths ofcirculation if it is to the advantage of the rotor to be cooled withoutdeparting from the spirit of this invention and this invention shall belimited only by the appended claims.

What we claim is:

1. A refrigerated centrifuge which includes an enclosing walled cabinet,having a base and a top cover, a plurality of refrigerated coilspositioned adjacent to the walls of said cabinet, a verticallypositioned rotor and supporting assembly for said rotor mounted in thecenter of said cabinet, a liner positioned to enclose said rotor andseparate said rotor from said refrigerating coils, said base of saidcabinet retaining a deflection plate positioned at an angle to the rotoraxis to direct the air stream from said rotor upward through therefrigerated coils, said deflection plate provided with a plurality ofinlet ports and baffles positioned on a horizontal plane adjacent thearea at which the air stream normally leaves said rotor, said bafesbeing positioned above said inlet ports, to direct a portion of the airflow through said inlet ports, said deection plate provided with aplurality of outlet ports adjacent the base of said rotor, saiddeflection plate dividing the air stream from said rotor into twolaminar flows, one of said air streams directed toward the bottom ofsaid rotor and the other directed upward and redirected to the top andsides of said rotor.

2. A refrigerated centrifuge which includes an enclosing walled cabinethaving a base and a top cover, a single vertically positioned centrifugerotor which is also the container for the medium to be separated mountedin the center of said cabinet, said rotor having angular outer walls andin which the base of said rotor has the greater dimension, a pluralityof refrigerated coils positioned adjacent the walls of said enclosingcabinet, an inner vertically positioned dividing wall to separate saidrefrigerated coils from said rotor, said rotor supported by a centralsupporting assembly, said dividing wall extending from a point slightlyabove the bottom of said rotor to the top of said cabinet which forms avertical air passage and provides an inlet at the bottom of saiddividing wall for the flow of air into said passage, a plurality ofoutlets positioned at the top of said dividing wall to direct the ow ofair out of said passage toward said rotor.

References Cited in the file of this patent yUNITED STATES PATENTS1,321,288 Dalzell Nov. 11, 1919 2,373,806 Barnes Apr, 17, 1945 2,699,289Allen et al. -.Jan. 11, 1955 2,854,189 Garrett Sept. 30, 1958

